Researchers have developed a new blood test that can detect autism early, before clear symptoms start appearing.
Carrying forward existing research, the Boston Children's Hospital team found that abnormal immunologic activity disturbing brain development may throw light on the origin of autism.
Autism spectrum disorder (ASD) is a developmental disorder that leads to significant social, communication and behavioral changes. Early diagnosis of autism means early intervention, hence efforts have been going on from a long time to identify the risk factors involved in the disorder.
According to the Centers for Disease Control and Prevention (CDC), about one in 88 children in the United States is affected by autism. Autism starts normally by the age of three and is diagnosed by the age of five. The finding is expected to be a breakthrough as till date no medical or blood test is available for the early diagnosis of the disorder. The child's behavior and development are some of the factors doctors use to determine the disorder.
For developing the test, Sek Won Kong from the Boston Children's Hospital Informatics Program (CHIP) and colleagues included 66 male patients with ASDs and 33 without the disorder. Blood samples from the ASD patients were collected and compared with participants without autism.
With the help of microarrays, they tried to identify RNA signatures with differences in gene activity and expression. Using the data, they identified 489 genes with distinctive expression patterns in autistic participants. Of the total genes, 55 genes were able to give an accurate autism diagnosis in 76 percent of samples.
The team again re-assured the accuracy of the test on 104 autistic patients and 82 without ASD.
"It's clear that no single mutation or even a single pathway is responsible for all cases," Dr. Isaac Kohane, director of CHIP and senior investigator of the study, said in a news release. "By looking at this 55-gene signature, which can capture disruptions in multiple pathways at once, we can say with about 70 percent accuracy, 'this child does not have autism,' or 'this child could be at risk,' putting him at the head of the queue for early intervention and evaluation. And we can do it relatively inexpensively and quickly."
Results of the study have been published Dec.5 in PLOS ONE.
